Abstract
The oil removal efficiency for the ex situ extraction of bitumen from oil sands, or ex situ washing of oil-contaminated sand and related processes is determined by the balance of forces at the oil/water and solid/fluid interfaces. The objective of this work is to estimate the balance of forces at the interface using dimensionless numbers, and their use in evaluating and engineering ex situ soil washing processes. To this end, bitumen was removed from bitumen-coated sand particles using a two-step process. In the first step, the particles were mixed with a suitable solvent (toluene) used, primarily, to reduce the viscosity of bitumen. The particles were then mixed with water or an aqueous surfactant solution capable of producing low interfacial tensions with the solvent-bitumen mixture. The fraction of oil retained after washing was evaluated as a function of interfacial tension, solvent/bitumen ratio, mixing time, mixing velocity, and particle size. These ex situ washing conditions were normalized using dimensionless film and particle-based Weber and Capillary numbers. The fraction of oil retained by the particles was plotted against these dimensionless numbers to generate capillary curves similar to those used in enhanced oil recovery. These curves reveal the existence of a critical film-based Weber number and a particle-based Capillary number that can be used in the design or evaluation of soil washing processes. The film-based Weber number also explained literature data that associates interfacial tension with the removal of oil from oil-based drill cuttings, as well as field observations on the role that particle size plays on the removal of oil in soil washing operations.
Similar content being viewed by others
References
Fingas M (2001) The basics of oil spill cleanup. Lewis Publishers, New York
Ornitz B, Champ M (2002) Oil spills first principles: prevention and best response. Elsevier, New York
Sittig M (1974) Oil spill prevention and removal handbook. Noyes Data Corporation, NJ
Breuel A (1981) Oil spill cleanup and protection techniques for shorelines and marshlands. Noyes Data Corporation, Park Ridge
Robert J (1990) Oil spill response guide. Noyes Data Corporation, Park Ridge
Tuler S, Webler T (2009) Stakeholder perspectives about marine oil spill response objectives: a comparative Q study of four regions. J Conting Crisis Manag 17:95–107
Canada Environment (1978) The impact and cleanup of oil spills on Canadian shorelines: a summary. Environmental Canada, Ottawa, ON
Acosta E, Harwell J, Scamehorn J, Sabatini D (2007) Application of microemulsions in cleaning technologies and environmental remediation. In: Johansson I, Somasundaran P (eds) Handbook for cleaning and decontamination of surfaces. Elsevier, Amsterdam, pp 831–884
Thompson L (1994) The role of oil detachment mechanisms in determining optimum detergency conditions. J Colloid Interface Sci 163:61–73
Rybinski W (2007) Physical aspects of cleaning processes. In: Johansson I, Somasundaran P (eds) Handbook for cleaning and decontamination of surfaces. Elsevier, Amsterdam, pp 1–55
Smith P, Van de Ven T (1985) The separation of a liquid drop from a stationary solid sphere in a gravitational field. J Colloid Interface Sci 105:1–20
Holmberg K (1998) Quarter century progress and new horizons in microemulsions. In: Shah DO (ed) Micelles, microemulsions, and monolayers. Marcel Dekker, New York, pp 161–192
Niven R, Khalili N, Hibbert D (2000) Mixed solid/dispersed phase particles in multiphase fluidized beds. Part 1. Chem Eng Sci 55:3013–3032
Niven R, Khalili N, Hibbert D (2000) Mixed solid/dispersed phase particles in multiphase fluidized beds. Part 2. Chem Eng Sci 55:3033–3051
Chang M, Huang C, Shu H (2000) Effects of surfactants on extraction of phenanthrene in spiked sand. Chemosphere 41:1295–1300
Bragato M, El Seoud O (2003) Formation, properties, and “ex situ” soil decontamination by vegetable oil-based microemulsions. J Surfactants Deterg 6:143–150
Childs J, Acosta E, Scamehorn J, Sabatini D (2005) Surfactant-enhanced treatment of drill cuttings. J Energy Res Technol 127:153–162
Khalladi R, Benhabiles O, Bentahar F, Moulai-Mostefa N (2009) Surfactant remediation of diesel fuel polluted soil. J Hazard Mater 164:1179–1184
Morris P, Tookey D, Walsh T (2005) The warren spring laboratory beach material washing plant for shoreline cleanup. In: Proceedings of the 2005 International Oil Spill Conference, p 9042
Pennell K, Pope G, Abriola L (1996) Influences of viscous and buoyancy forces on the mobilization of residual tetrachloroethylene during surfactant flushing. Environ Sci Technol 20:1328–1335
Childs J, Acosta E, Knox R, Harwell J, Sabatini D (2004) Improving the extraction of tetrachloroethylene from soil columns using surfactant gradient systems. J Contam Hydrol 71:27–45
Anton L, Hilfer R (1999) Trapping and mobilization of residual fluid during capillary desaturation in porous media. Phys Rev E 59:6819–6823
Walstra P (1993) Principles of emulsion formation. Chem Eng Sci 48:333–349
Kiran S, Acosta E, Moran K (2009) Study of solvent-bitumen-water rag layers. Energy Fuels 23:3139–3149
Mossop G (1980) Geology of the Athabasca oil sands. Science 207:145–152
Kiran S, Acosta E, Moran K (2009) Evaluating the hydrophilic-lipophilic nature of asphaltenic oils and naphthenic amphiphiles using microemulsion models. J Colloid Interface Sci 336:304–313
Bird R, Stewart W, Lightfoot E (2002) Transport phenomena, 2nd edn. John Wiley, New York
Swank R, Roth G (1954) Apparatus for measuring relative blood viscosity. Rev Sci Instrum 25:1020–1022
Acosta E, Szekeres E, Harwell J, Grady B, Sabatini D (2009) Morphology of ionic microemulsions: comparison of SANS studies and the net-average curvature (NAC) model. Soft Matter 5:551–561
Rosen M (2004) Surfactants and interfacial phenomena. Wiley-Interscience, Hoboken
Acosta E, Harwell J, Sabatini D (2004) Self-assembly in linker-modified microemulsions. J Colloid Interface Sci 274:652–664
Angle C, Lue L, Dabros T, Hamza H (2005) Viscosities of heavy oils in toluene and partially deasphalted heavy oils in heptol in a study of asphaltenes self-interactions. Energy Fuels 19:2014–2020
Fan E, Bussmann M, Acosta E (2011) Equilibrium positions of drops attached to spheres immersed in a uniform laminar flow. Can J Chem Eng 89:707–716
Tongcumpou C, Acosta E, Quencer L, Joseph A, Scamehorn J, Sabatini D, Yanumet N, Chavadej S (2005) Microemulsion formation and detergency with oily soils: III. performance and mechanisms. J Surfactants Deterg 8:147–156
Dai D, Chung K (1995) Bitumen-sand interaction in oil sand processing. Fuel 74:1858–1864
Spelt P (2006) Shear flow past two-dimensional droplets pinned or moving on an adhering channel wall at moderate Reynolds numbers: a numerical study. J Fluid Mech 561:439–463
US Environmental Protection Agency (EPA) (2012) Cost and performance report: soil washing at the King of Prussia technical corporation superfund site. http://www.clu-in.org/products/costperf/SOILWASH/Kop.htm. Accessed 18 Mar 2014
Vertase FLI Ltd. (2012) Soil washing (Scrubbing). http://www.vertasefli.co.uk/soil-washing-c53.html. Accessed 18 Mar 2014
Acknowledgments
We would like to thank the American Chemical Society-Petroleum Research Fund and the Natural Sciences and Engineering Research Council of Canada (NSERC) for their financial support and Syncrude Canada for providing bitumen samples.
Author information
Authors and Affiliations
Corresponding author
About this article
Cite this article
Quraishi, S., Bussmann, M. & Acosta, E. Capillary Curves for Ex-situ Washing of Oil-Coated Particles. J Surfact Deterg 18, 811–823 (2015). https://doi.org/10.1007/s11743-015-1704-8
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s11743-015-1704-8